After marrying Macdonald in Kingston, Ontario in 1843, she enjoyed two years of happy marriage before falling seriously ill.

[1] Macdonald took an immediate liking to Isabella, suggesting she should visit Kingston the following year, ostensibly to see another of her sisters, Maria, who had married John Alexander Macpherson.

[2][3] It was on this trip that after a few months courting, they were engaged and finally married on September 1, 1843, at the home of her sister, Maria and brother-in-law John Alexander Macpherson with the Rev.

John took her to New York to see if the doctors there were able to help her, and she would escape the cold climate of Kingston, Ontario by visiting her sister in Savannah, Georgia for a few months at a time.

John rented Bellevue House, a home in the Western Liberties neighborhood of Kingston (a quieter, cleaner area of town) as a restful space for Isabella to improve her health, and recover.